Ecological impact assessment of metallurgic effluents using in situ biomarker assays

An ecological impact study was performed based on in situ biomarker assays with the waterflea Daphnia magna. The effects of metallurgic effluents on the energy metabolism, anti-oxidative metabolism and DNA damage were assessed in caged daphnids during a 4-week study. In situ survival and reproduction studies demonstrated a clear impact on these parameters in organisms exposed in the most polluted areas. At the downstream--sublethal--zone the organisms were disturbed within their tolerance limits, resulting in alterations of their energy metabolism. These data suggest an acclimation hypothesis, which was tested through the analysis of the energy metabolism of resident species: isopods and amphipods. These organisms had shifted to a decrease in their overall energy metabolism compared to the upstream region. This change in some biochemical processes suggests a selective advantage to cope with the prevailing environmental conditions. In addition, we found clear genotoxic effects caused by the industrial discharges that might correlate with a reduction in (long-term) survival.     

Role of peat organic matter on isotopic composition of most abundant benthic organisms in intertidal habitats of SW Iceland

The transfer of peat organic matter (OM) from tidal pools of upper littoral to downstream rocky shores and its potential incorporation into marine biota were investigated using the stable isotope approach. Samplings were carried out in September 2004 in two SW Icelandic sites (Osar and Hvassahraun), where we selected (1) areas with shores where grass gently declined towards rocks and, on reaching the sea line, formed small tidal peat pools and (2) areas where grass and rocky shores were not contiguous, rather the grass lower limits were several hundreds of meters back from the shore. In both grass and no grass areas, in the intertidal zone, all benthic organisms and all potential OM sources were sampled. Dominant macroalgae were Ascophyllum nodosum ([Linnaeus] Le Jolis) and Fucus vesiculosus Linnaeus. In grass sites, organisms partially reflected the isotopic composition of peat OM, while in no grass sites, peat represented only a negligible amount of available OM, or its signal was totally absent from the environment. Intertidal organisms could rely on peat both directly by suspension feeding, grazing or scavenging and indirectly by predation (crabs) on low level consumers (barnacles).     

Sustainability of sand dune restoration along the coast of the Tyrrhenian sea

This study reports the results of restoration management on sand dune environments along the coastal belt of the Castelporziano nature reserve (Rome, Italy) and the subsequent monitoring phases to test the sustainability of the ‘soft techniques’ applied. In the area concerned, over a length of ca. 3 km, 40 dunes were built up along with three belts located at <40 m, 40–70 m, and >70 m, respectively, from the shoreline. On each of 38 dunes 20 individuals ofAmmophila littoralis were planted; this species is one of the local autochthonous species considered particularly suitable for stabilizing sand dunes. After one year, two years and five years, respectively the changes in height and surface of each dune, the survival rates ofA. littoralis, and its changes in cover, the appearance of new shoots and the establishment of new species were observed. A progressive increase in species number, which five years after the restoration amounted to about 60% of those characterizing the natural dunes, was reported indicating a progressive trend towards populations similar to natural ones. In the colonization of new species there is a prevalence of theSporobolus-Elymetum farcti and theSalsolo Kali-Cakiletum maritimae association, while the species established successively refer to theEchinophoro spinosae-Ammophiletum arundinaceae association and theCrucianellion maritimae alliance as occurring in natural successions. This succession runs parallel to the natural dune colonization processes. In particular, the data regarding survival, cover and number of vegetative shoots indicate that the dune belt between 40 and 70 m from the sea is the one most suitable for restoration. Some changes in dune morphology was observed: the height of the artificial dunes tended to decrease considerably in the five years of observation, whereas a progressive increase in their surface area was observed. During the study period.A littoralis favoured the establishment of new species, but as yet exercises no action on increasing dune height.     

A framework for habitat monitoring and climate change modelling: construction and validation of the Environmental Stratification of Estonia

Environmental stratifications provide the framework for efficient surveillance and monitoring of biodiversity and ecological resources, as well as modelling exercises. An obstacle for agricultural landscape monitoring in Estonia has been the lack of a framework for the objective selection of monitoring sites. This paper describes the construction and testing of the Environmental Stratification of Estonia (ESE). Principal components analysis was used to select the variables that capture the most amount of variation. Seven climate variables and topography were selected and subsequently subjected to the ISODATA clustering routine in order to produce relatively homogeneous environmental strata. The ESE contains eight strata, which have been described in terms of soil, land cover and climatic parameters. In order to assess the reliability of the stratification procedure for the selection of monitoring sites, the ESE was compared with the previous map of Landscape Regions of Estonia and correlated with five environmental data sets. All correlations were significant. The stratification has therefore already been used to extend the current series of samples in agricultural landscapes into a more statistically robust series of monitoring sites. The potential for applying climate change scenarios to assess the shifts in the strata and associated ecological impacts is also examined.     

Genotoxic and melanic alterations in Lithobates catesbeianus (anura) tadpoles exposed to fipronil insecticide

Environmental Science and Pollution Research - The aim of this study was to evaluate the genotoxic and morphological systemic effects of both an acute and a chronic exposure of bullfrog tadpoles to...     

Environmental risk assessment of metals: tools for incorporating bioavailability

In this paper, some of the main processes and parameters which affect metal bioavailability and toxicity in the aquatic environment and its implications for metal risk assessment procedures will be discussed. It has become clear that, besides chemical processes (speciation, complexation), attention should also be given to physiological aspects for predicting metal toxicity. The development of biotic ligand models (BLMs), which combine speciation models with more biologically oriented models (e.g. GSIM), has offered an answer to this need. The various BLMs which have been developed and/or refined for a number of metals (e.g. Cu, Ag, Zn) and species (algae, crustaceans, fish) are discussed here. Finally, the potential of the BLM approach is illustrated through a theoretical exercise in which chronic zinc toxicity to Daphnia magna is predicted in three regions, taking the physico-chemical characteristics of these areas into account.     

基于风量-风压复合特征的通风系统阻变型故障诊断

为了避免风量单一特征进行故障位置诊断的不适定性,提出基于风量-风压复合特征的故障位置诊断方法,实现特征信息的多维互补,提高故障位置诊断的准确度。利用蒙特卡洛方法生成大致满足实际故障风阻值分布的故障仿真样本,为了避免不同变量之间不同量纲、不同数量级造成的数据损失,对原始风量、风压数据进行标准化处理,并分别以风量单一特征、风压单一特征、风量-风压复合特征作为支持向量机（SVM）的输入,构建通风系统阻变型故障位置诊断模型。通过故障模拟实验研究表明:风量、风压单一特征进行故障位置诊断的准确度分别为89.80%,90.34%,风量-风压复合特征进行故障位置诊断的准确度为98.23%,说明风量-风压复合特征进行故障诊断可以消除风量、风压单一特征进行故障诊断的不适定性,提高故障诊断的准确度。     

空气-乙炔火焰原子吸收法测铬时的干扰及消除

对空气-乙炔火焰原子吸收法测铬(Cr)时共存元素对其测定结果的干扰进行研究。结果表明,当ρ(共存元素)/ρ(Cr)100时,Mg、Co、Al、V、Ni、Fe、Na、Ca对Cr测定有影响,而K、Mn、Zn、Mo、Pb、Si、Cu均不影响Cr的测定;当ρ(共存元素)/ρ(Cr)为10和30时,加入1%HNO_3和2%NH_4Cl可消除干扰;当ρ(共存元素)/ρ(Cr)30时,加入5%HCl和超过1%的NH_4Cl可消除干扰;5%HCl作为介质消除Cr测定干扰的效果要优于1%HNO_3介质。     

Structure and function of the eversible organs of several genera of larval firefly (Coleoptera: Lampyridae)

Larval defensive behaviour and eversible organ morphology were compared in the firefly species Luciola cruciata Motschulsky 1854, L. lateralis Motschulsky 1860, L. leii Fu et Ballantyne 2006, Lampyris noctiluca Linnaeus 1767, Pyrocoelia analis Fabricius 1801, P. pectoralis Oliver 1883, P. sp. and two Diaphanes species. In all cases the eversible organs are located on the pleural cuticle, dorsal to the spiracle, but there is considerable variation between species in their number, size and shape. In La. noctiluca they are confined to the abdomen, whereas in the other species they also occur on the meta- and mesothorax. In La. noctiluca and the Pyrocoelia species the organs are columnar in shape, contrasting with the forked organs of the Luciola and Diaphanes species. The eversible organs of the Luciola species, which are all aquatic, are remarkably larger (relative to body length) than those of the other, terrestrial species. On organ eversion the Luciola species emit an odour resembling pine oil, the Diaphanes species smell weakly of mint and L. noctiluca and the Pyrocoelia species produce no discernible scent, though ants are nonetheless repelled by contact with everted L. noctiluca organs. The organs of all the species studied support protuberances on their external surface, though these too vary in shape, size and ornamentation between species. In all species except L. noctiluca each protuberance is connected to a well-developed globular body via a long, thick stalk. Circular foveae are located in the centres of these globular bodies. The globular bodies consist of secretory cells characterized by the presence of numerous mitochondria and an extensive system of cisternae and tubular endoplasmic reticulum. Behavioural tests revealed that small larvae run away instead of becoming immobile and glowing, whereas large larvae start to glow when disturbed. The study shows that the eversible larval organs form an important part of a defensive arsenal in the Lampyridae.